Ladder

• US 20050056489A1
• Filed: 10/14/2003
• Published: 03/17/2005
• Est. Priority Date: 10/14/2002
• Status: Active Grant

• Current Assignee: Branach Technology Pty Ltd
• Original Assignee: Branach Technology Pty Ltd
• Inventors: Walsh, Michael P.
• Granted Patent: US 7,104,361 B2
• Time in Patent Office: Days
• US Class Current: 182/156
• CPC Class Codes: E06C 1/393 Ladders having platforms foldable with the ladder
• CPC Class Codes: E06C 7/14 Holders for pails or other equipment on or for ladders
• CPC Class Codes: E06C 7/182 situated at the top of the ladder
• CPC Class Codes: E06C 7/185 Devices providing a back support to a person on the ladder, e.g. cages

Abstract

A platform ladder comprising two elongate ladder sections having feet at one end and an upper end, the upper end of each section being hinged to an upper rail, a platform pivotally secured to one ladder section below the upper end and adapted to interconnect with the other ladder section, and stays interconnecting each side of the ladder sections whereby when the ladder is in an operative position with the ladder sections assuming an erect A shaped profile with the platform extending between the ladder sections to define a standing platform, the ladder sections, upper rail and stays, define a four bar linkage.

Claims

1. A platform ladder comprising two elongate ladder sections having feet at one end and an upper end, the upper end of each section being hinged to an upper rail, a platform pivotally secured to one ladder section below the upper end and adapted to interconnect with the other ladder section, and stays interconnecting each side of the ladder sections whereby when the ladder is in an operative position with the ladder sections assuming an erect A shaped profile with the platform extending between the ladder sections to define a standing platform, the ladder sections, upper rail and stays, define a four bar linkage.

2. The platform ladder according to claim 1 wherein the upper rail constitutes a safety barrier that is above the platform to, in use, be at approximately the hip height of a user of the ladder when standing on the platform.

3. The platform ladder according to claim 1 wherein the ladder is foldable for transportation whereby the ladder sections rest one against the other.

4. The platform ladder according to claim 3 wherein, in the folded configuration, the platform and upper rail fold within the plane defined by the ladder sections.

5. The platform ladder according to claim 1 wherein the platform is coupled to the other ladder section by at least one platform stay whereby as the ladder sections are parted from the folded configuration the platform stay controls a lowering of the platform until it engages the other ladder section when the sections are fully parted to assume the operative position.

6. The platform ladder according to claim 5 where a retarder is positioned between the platform and the platform stay to retard the relative movement and slow down the engagement of the platform with the other ladder section.

7. The platform ladder according to claim 1 wherein the upper rail includes interfitting sections that from a closed loop to surround the user.

8. The ladder according to claim 7 wherein the upper rail has lateral sides extending between the ladder sections and a cross section extending across the rear ladder section, a U shaped arm being pivotally secured across the lateral sides of the front ladder section, the arm being in two pieces that can be latched together to close the rail or be opened and pivoted clear of the front section to provide access.

9. The platform ladder according to claim 1 wherein each ladder section comprises elongate fiberglass stiles joined by spaced aluminum rungs.

10. A platform ladder comprising two elongate ladder sections having feet at one end and an upper end, the upper end of each section being hinged to an upper rail, a platform pivotally secured to one ladder section below the upper end and adapted to interconnect with the other ladder section, and stays interconnecting each side of the ladder sections whereby when the ladder is in an erect A shaped profile to define a standing platform, the ladder sections, upper rail and stays, define a four bar linkage, and when the ladder is folded for transportation, the ladder sections rest one against the other and the platform and upper rail fold with the plane defined by the ladder sections.